1. Field of the Invention
This invention is in the field of snow and ice melting equipment and more particularly relates to the melting of passages through ice dams which form on building eaves so as to relieve the dammed water and prevent damage caused by this water leaking into the building.
2. Description of the Prior Art
A common problem with buildings, including houses, in the colder climates has been the buildup of ice near eaves and a consequent damming of the melted snow above above the buildup. Snow on the central portion of the roof is melted by a combination of the sun's energy and heat conducted through the roof from the warm living quarters. This melt flows down the roof to the eaves where some of it is absorbed by the snow there. The eaves are frequently colder than the upper portion of the roof because of reduced heating from the interior of the building and this soggy snow freezes into dense blocks called ice dams. Large puddles of melt are created behind these dams and sometimes extend up into the overlapping shingles far enough to damage shingles and cause severe leaking into the house. This often results in significant damage to the interior structure, finishing, and furnishings.
The usual method for relieving this problem is chopping the ice away and allowing the water to run off. This operation, high on an ice covered roof, is dangerous, and must be repeated fairly frequently. Additionally, unless care is exercised, the roof shingles will be damaged.
A second method of preventing damage is the installation of wide metal flashing along and extending above the eaves. This does not prevent the ice dams, but usually keeps the water from leaking into the house by providing a continuous barrier to the water. The installation is expensive and sometimes unattractive.
Another common method of deafeating these ice dams is the installation of electric heating wires on the roof at the eaves. This is generally very effective at breaking the dams, but the units are fairly expensive to purchase and install. Attention must be paid to the snow conditions on the roof in order to switch power on and off when necessary. Frequently the electricity is left going throughout the winter, consuming a considerable amount of electric energy. The wires also present an electric shock and fire hazard.